usbhw.c

LPCXpresso1768

 *                       EPNum.0..3: Address
 *                       EPNum.7:    Dir
 *                     pData: Pointer to Data Buffer
 *    Return Value:    Number of bytes read
 */

uint32_t USB_ReadEP (uint32_t EPNum, uint8_t *pData) {
  uint32_t cnt, n;

  LPC_USB->Ctrl = ((EPNum & 0x0F) << 2) | CTRL_RD_EN;

  do {
    cnt = LPC_USB->RxPLen;
  } while ((cnt & PKT_RDY) == 0);
  cnt &= PKT_LNGTH_MASK;

  for (n = 0; n < (cnt + 3) / 4; n++) {
    *((__attribute__((packed)) uint32_t *)pData) = LPC_USB->RxData;
    pData += 4;
  }
  LPC_USB->Ctrl = 0;

  if (((EP_MSK_ISO >> EPNum) & 1) == 0) {   /* Non-Isochronous Endpoint */
    WrCmdEP(EPNum, CMD_CLR_BUF);
  }
  return (cnt);
}


/*
 *  Write USB Endpoint Data
 *    Parameters:      EPNum: Endpoint Number
 *                       EPNum.0..3: Address
 *                       EPNum.7:    Dir
 *                     pData: Pointer to Data Buffer
 *                     cnt:   Number of bytes to write
 *    Return Value:    Number of bytes written
 */

uint32_t USB_WriteEP (uint32_t EPNum, uint8_t *pData, uint32_t cnt) {
  uint32_t n;

  LPC_USB->Ctrl = ((EPNum & 0x0F) << 2) | CTRL_WR_EN;

  LPC_USB->TxPLen = cnt;

  for (n = 0; n < (cnt + 3) / 4; n++) {
    LPC_USB->TxData = *((__attribute__((packed)) uint32_t *)pData);
    pData += 4;
  }
  LPC_USB->Ctrl = 0;
  WrCmdEP(EPNum, CMD_VALID_BUF);
  return (cnt);
}

#if USB_DMA

/* DMA Descriptor Memory Layout */
const uint32_t DDAdr[2] = { DD_NISO_ADR, DD_ISO_ADR };
const uint32_t DDSz [2] = { 16,          20         };


/*
 *  Setup USB DMA Transfer for selected Endpoint
 *    Parameters:      EPNum: Endpoint Number
 *                     pDD: Pointer to DMA Descriptor
 *    Return Value:    TRUE - Success, FALSE - Error
 */

uint32_t USB_DMA_Setup(uint32_t EPNum, USB_DMA_DESCRIPTOR *pDD) {
  uint32_t num, ptr, nxt, iso, n;

  iso = pDD->Cfg.Type.IsoEP;                /* Iso or Non-Iso Descriptor */
  num = EPAdr(EPNum);                       /* Endpoint's Physical Address */

  ptr = 0;                                  /* Current Descriptor */
  nxt = udca[num];                          /* Initial Descriptor */
  while (nxt) {                             /* Go through Descriptor List */
    ptr = nxt;                              /* Current Descriptor */
    if (!pDD->Cfg.Type.Link) {              /* Check for Linked Descriptors */
      n = (ptr - DDAdr[iso]) / DDSz[iso];   /* Descriptor Index */
      DDMemMap[iso] &= ~(1 << n);           /* Unmark Memory Usage */
    }
    nxt = *((uint32_t *)ptr);                  /* Next Descriptor */
  }

  for (n = 0; n < 32; n++) {                /* Search for available Memory */
    if ((DDMemMap[iso] & (1 << n)) == 0) {
      break;                                /* Memory found */
    }
  }
  if (n == 32) return (FALSE);              /* Memory not available */

  DDMemMap[iso] |= 1 << n;                  /* Mark Memory Usage */
  nxt = DDAdr[iso] + n * DDSz[iso];         /* Next Descriptor */

  if (ptr && pDD->Cfg.Type.Link) {
    *((uint32_t *)(ptr + 0))  = nxt;           /* Link in new Descriptor */
    *((uint32_t *)(ptr + 4)) |= 0x00000004;    /* Next DD is Valid */
  } else {
    udca[num] = nxt;                        /* Save new Descriptor */
    UDCA[num] = nxt;                        /* Update UDCA in USB */
  }

  /* Fill in DMA Descriptor */
  *((uint32_t *)nxt) =  0;                 /* Next DD Pointer */
  nxt++;                 /* Next DD Pointer */
  *((uint32_t *)nxt) =  pDD->Cfg.Type.ATLE |
                       (pDD->Cfg.Type.IsoEP << 4) |
                       (pDD->MaxSize <<  5) |
                       (pDD->BufLen  << 16);
  nxt++;                 /* Next DD Pointer */
  *((uint32_t *)nxt) =  pDD->BufAdr;
  nxt++;                 /* Next DD Pointer */
  *((uint32_t *)nxt) =  pDD->Cfg.Type.LenPos << 8;
  nxt++;                 /* Next DD Pointer */
  if (iso) {
    *((uint32_t *)nxt) =  pDD->InfoAdr;
  }

  return (TRUE); /* Success */
}


/*
 *  Enable USB DMA Endpoint
 *    Parameters:      EPNum: Endpoint Number
 *                       EPNum.0..3: Address
 *                       EPNum.7:    Dir
 *    Return Value:    None
 */

void USB_DMA_Enable (uint32_t EPNum) {
  LPC_USB->EpDMAEn = 1 << EPAdr(EPNum);
}


/*
 *  Disable USB DMA Endpoint
 *    Parameters:      EPNum: Endpoint Number
 *                       EPNum.0..3: Address
 *                       EPNum.7:    Dir
 *    Return Value:    None
 */

void USB_DMA_Disable (uint32_t EPNum) {
  LPC_USB->EpDMADis = 1 << EPAdr(EPNum);
}


/*
 *  Get USB DMA Endpoint Status
 *    Parameters:      EPNum: Endpoint Number
 *                       EPNum.0..3: Address
 *                       EPNum.7:    Dir
 *    Return Value:    DMA Status
 */

uint32_t USB_DMA_Status (uint32_t EPNum) {
  uint32_t ptr, val;
          
  ptr = UDCA[EPAdr(EPNum)];                 /* Current Descriptor */
  if (ptr == 0) 
	return (USB_DMA_INVALID);

  val = *((uint32_t *)(ptr + 3*4));            /* Status Information */
  switch ((val >> 1) & 0x0F) {
    case 0x00:                              /* Not serviced */
      return (USB_DMA_IDLE);
    case 0x01:                              /* Being serviced */
      return (USB_DMA_BUSY);
    case 0x02:                              /* Normal Completition */
      return (USB_DMA_DONE);
    case 0x03:                              /* Data Under Run */
      return (USB_DMA_UNDER_RUN);
    case 0x08:                              /* Data Over Run */
      return (USB_DMA_OVER_RUN);
    case 0x09:                              /* System Error */
      return (USB_DMA_ERROR);
  }

  return (USB_DMA_UNKNOWN);
}


/*
 *  Get USB DMA Endpoint Current Buffer Address
 *    Parameters:      EPNum: Endpoint Number
 *                       EPNum.0..3: Address
 *                       EPNum.7:    Dir
 *    Return Value:    DMA Address (or -1 when DMA is Invalid)
 */

uint32_t USB_DMA_BufAdr (uint32_t EPNum) {
  uint32_t ptr, val;

  ptr = UDCA[EPAdr(EPNum)];                 /* Current Descriptor */
  if (ptr == 0)
  {
	return ((uint32_t)(-1));                /* DMA Invalid */
  }

  val = *((uint32_t *)(ptr + 2*4));         /* Buffer Address */
  return (val);                             /* Current Address */
}


/*
 *  Get USB DMA Endpoint Current Buffer Count
 *   Number of transfered Bytes or Iso Packets
 *    Parameters:      EPNum: Endpoint Number
 *                       EPNum.0..3: Address
 *                       EPNum.7:    Dir
 *    Return Value:    DMA Count (or -1 when DMA is Invalid)
 */

uint32_t USB_DMA_BufCnt (uint32_t EPNum) {
  uint32_t ptr, val;

  ptr = UDCA[EPAdr(EPNum)];                 /* Current Descriptor */
  if (ptr == 0)
  { 
	return ((uint32_t)(-1));                /* DMA Invalid */
  }
  val = *((uint32_t *)(ptr + 3*4));         /* Status Information */
  return (val >> 16);                       /* Current Count */
}


#endif /* USB_DMA */


/*
 *  Get USB Last Frame Number
 *    Parameters:      None
 *    Return Value:    Frame Number
 */

uint32_t USB_GetFrame (void) {
  uint32_t val;

  WrCmd(CMD_RD_FRAME);
  val = RdCmdDat(DAT_RD_FRAME);
  val = val | (RdCmdDat(DAT_RD_FRAME) << 8);

  return (val);
}


/*
 *  USB Interrupt Service Routine
 */

void USB_IRQHandler (void) {
  uint32_t disr, val, n, m;
  uint32_t episr, episrCur;

  disr = LPC_USB->DevIntSt;       /* Device Interrupt Status */

  /* Device Status Interrupt (Reset, Connect change, Suspend/Resume) */
  if (disr & DEV_STAT_INT) {
    LPC_USB->DevIntClr = DEV_STAT_INT;
    WrCmd(CMD_GET_DEV_STAT);
    val = RdCmdDat(DAT_GET_DEV_STAT);       /* Device Status */
    if (val & DEV_RST) {                    /* Reset */
      USB_Reset();
#if   USB_RESET_EVENT
      USB_Reset_Event();
#endif
    }
    if (val & DEV_CON_CH) {                 /* Connect change */
#if   USB_POWER_EVENT
      USB_Power_Event(val & DEV_CON);
#endif
    }
    if (val & DEV_SUS_CH) {                 /* Suspend/Resume */
      if (val & DEV_SUS) {                  /* Suspend */
        USB_Suspend();
#if     USB_SUSPEND_EVENT
        USB_Suspend_Event();
#endif
      } else {                              /* Resume */
        USB_Resume();
#if     USB_RESUME_EVENT
        USB_Resume_Event();
#endif
      }
    }
    goto isr_end;
  }

#if USB_SOF_EVENT
  /* Start of Frame Interrupt */
  if (disr & FRAME_INT) {
    USB_SOF_Event();
  }
#endif

#if USB_ERROR_EVENT
  /* Error Interrupt */
  if (disr & ERR_INT) {
    WrCmd(CMD_RD_ERR_STAT);
    val = RdCmdDat(DAT_RD_ERR_STAT);
    USB_Error_Event(val);
  }
#endif

  /* Endpoint's Slow Interrupt */
  if (disr & EP_SLOW_INT) {
    episrCur = 0;
    episr    = LPC_USB->EpIntSt;
    for (n = 0; n < USB_EP_NUM; n++) {      /* Check All Endpoints */
      if (episr == episrCur) break;         /* break if all EP interrupts handled */
      if (episr & (1 << n)) {
        episrCur |= (1 << n);
        m = n >> 1;
  
        LPC_USB->EpIntClr = (1 << n);
        while ((LPC_USB->DevIntSt & CDFULL_INT) == 0);
        val = LPC_USB->CmdData;
  
        if ((n & 1) == 0) {                 /* OUT Endpoint */
          if (n == 0) {                     /* Control OUT Endpoint */
            if (val & EP_SEL_STP) {         /* Setup Packet */
              if (USB_P_EP[0]) {
                USB_P_EP[0](USB_EVT_SETUP);
                continue;
              }
            }
          }
          if (USB_P_EP[m]) {
            USB_P_EP[m](USB_EVT_OUT);
          }
        } else {                            /* IN Endpoint */
          if (USB_P_EP[m]) {
            USB_P_EP[m](USB_EVT_IN);
          }
        }
      }
    }
    LPC_USB->DevIntClr = EP_SLOW_INT;
  }

#if USB_DMA

  if (LPC_USB->DMAIntSt & 0x00000001) {          /* End of Transfer Interrupt */
    val = LPC_USB->EoTIntSt;
    for (n = 2; n < USB_EP_NUM; n++) {      /* Check All Endpoints */
      if (val & (1 << n)) {
        m = n >> 1;
        if ((n & 1) == 0) {                 /* OUT Endpoint */
          if (USB_P_EP[m]) {
            USB_P_EP[m](USB_EVT_OUT_DMA_EOT);
          }
        } else {                            /* IN Endpoint */
          if (USB_P_EP[m]) {
            USB_P_EP[m](USB_EVT_IN_DMA_EOT);
          }
        }
      }
    }
    LPC_USB->EoTIntClr = val;
  }

  if (LPC_USB->DMAIntSt & 0x00000002) {          /* New DD Request Interrupt */
    val = LPC_USB->NDDRIntSt;
    for (n = 2; n < USB_EP_NUM; n++) {      /* Check All Endpoints */
      if (val & (1 << n)) {
        m = n >> 1;
        if ((n & 1) == 0) {                 /* OUT Endpoint */
          if (USB_P_EP[m]) {
            USB_P_EP[m](USB_EVT_OUT_DMA_NDR);
          }
        } else {                            /* IN Endpoint */
          if (USB_P_EP[m]) {
            USB_P_EP[m](USB_EVT_IN_DMA_NDR);
          }
        }
      }
    }
    LPC_USB->NDDRIntClr = val;
  }

  if (LPC_USB->DMAIntSt & 0x00000004) {          /* System Error Interrupt */
    val = LPC_USB->SysErrIntSt;
    for (n = 2; n < USB_EP_NUM; n++) {      /* Check All Endpoints */
      if (val & (1 << n)) {
        m = n >> 1;
        if ((n & 1) == 0) {                 /* OUT Endpoint */
          if (USB_P_EP[m]) {
            USB_P_EP[m](USB_EVT_OUT_DMA_ERR);
          }
        } else {                            /* IN Endpoint */
          if (USB_P_EP[m]) {
            USB_P_EP[m](USB_EVT_IN_DMA_ERR);
          }
        }
      }
    }
    LPC_USB->SysErrIntClr = val;
  }

#endif /* USB_DMA */

isr_end:
  return;
}